Book 2 for my 2026 goal of 36 books for the year! As is now default for me, my link to the book is through my bookshop dot org affiliate account.

One joy of being active on social media — in the midst of a lot of downsides — is becoming friends with authors and getting to read their books. A few years ago, I picked up journalist and internet friend Mark Sumner’s 2016 science fiction novel On Whetsday; I lost track of it among a pile of books for a while, but finally settled in to read it this week and absolutely loved it.

Long ago, a race of beings known as the cithians (seen on the cover) rescued the last remnants of humanity from a disaster that rendered the Earth uninhabitable. Since then, the small number of humans have been cared for by their cithian hosts on the planet Rask, being fed and housed in special districts and only being asked to follow a small number of simple rules.

Denny is a young man who lives in the city of Jukal Plex with about a dozen fellow humans, who have become his de facto family; others have been relocated to other cities on the planet. Denny has little to do but try to earn a few credits for luxuries by dancing at the city spaceport. None of the other alien species dances like humans do, so Denny can often get donations from curious spectators. On one Whetsday, a chug leaves Denny a strange glowing cube as a tip, an object that Denny does not recognize.

Denny’s curiosity about the cube takes him to a number of his fellow humans, most of whom known nothing about the object. The ones who do, however, tell him in fearful whispers that possessing it is forbidden. Denny probes further, and his efforts lead him to a secret long held by the cithians that could lead to the end of his adopted family. And possibly humanity.

On Whetsday is a relatively short book, but it is a compelling read and packs a surprising punch. The first few chapters start slowly because the book has to set up a radically different vision of the future and humanity, in which we are struggling refugees in an interplanetary society. Once Denny’s investigations lead him to unpleasant revelations, the book becomes absolutely impossible to put down. I read the entire second half of the book last night in one sitting, because at that point I had become so invested in the fate of the characters that I couldn’t step away.

The central secret of the book is a really fascinating twist and one that I did not see coming, and a rather profound one at that. It touches upon omnipresent xenophobia and “fear and hatred of the other” but from a perspective I hadn’t seen before. It is also a very satisfying revelation that puts everything one has learned throughout the book to that point in a different light.

The worldbuilding is impressive, and I really felt like I could see the planet Rask and its inhabitants; we learn a lot about cithian biology as the story progresses and it ends up playing a significant role later in the book.

If you’re looking for a fascinating, beautiful and cleverly written science fiction novel, I can highly recommend On Whetsday!